Working PaperCities

Demystifying Compact Urban Growth: Evidence From 300 Studies From Across the World

Gabriel Ahlfeldt, Elisabetta Pietrostefani

Most developed countries now pursue policies that implicitly or explicitly aim at promoting compact urban form. This report analyses more than 300 academic papers that study the effects of compact urban form.

Authors

Gabriel Ahlfeldt OECD

Elisabetta Pietrostefani OECD

Overview

September 2017

Most developed countries now pursue policies that implicitly or explicitly aim at promoting compact urban form. This report analyses more than 300 academic papers that study the effects of compact urban form, and finds that 69% of the papers reviewed find positive effects associated with compact urban form. Over 70% of studies find positive effects of economic density (the number of people living or working in an area). A smaller majority of studies attribute positive effects to mixed land use (58%) and the density of the built environment (56%).

These averages hide significant variation across specific dimensions of urban development. In order to understand the effects of compact urban form, the report estimates the monetary per capita value of the change in 15 outcomes in response to a 10% change in economic density. The major benefits of economic density arise from improved productivity and better access to jobs and services. Further benefits are generated through the preservation of urban green space, greater energy efficiency, pollution reduction and safer urban environments. The major costs of higher economic density are related to congestion, health and well-being. Increasing compactness can also contribute to higher land values and housing costs, which are borne disproportionately by renters and first-time buyers.

Increasing economic density therefore requires accompanying policy interventions to maximise the benefits and minimise the costs associated with compactness. In particular, policymakers need to facilitate large-scale investment in housing supply and public transport networks to ensure efficient and equitable access to housing, services and jobs in compact cities.

Better Urban Growth in Tanzania: A Preliminary Exploration of the Opportunities and Challenges

Tanzania has the sixth highest rate of urban population growth in the world, but so far it has been largely informal and unmanaged. This paper offers recommendations for managing Tanzania’s urban growth at the country level.

Better Cities, Better Growth: India’s Urban Opportunity

Meenu Tewari, Nick Godfrey

CitiesRegion & Country Studies

India is experiencing an urban transformation. Given the rapidity of change and the long-lived nature of urban form and infrastructure, the decisions that India’s policy-makers take in the next 5–15 years will lock in its urban pathway for decades to come.

Nick Godfrey, Xiao Zhao

CitiesFinance

In urban infrastructure the investment decisions taken today will shape tomorrow. Despite the critical importance of infrastructure for urban development, financing to scale up smarter, more sustainable urban infrastructure remains an immense challenge, particularly in emerging and developing economies.